Hosea e



(No Model.)

H. R. TILLISON.

CUTTER HEAD.

Patented Nov. 9, 1897.

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UNITED STATES PATENT OFFICE.

IIOSEA R. TILLISON, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE S. A.

' l/VOODS MACHINE COMPANY, OF SAME PLACE.

CUTTER-HEAD.

SPECIFICATION forming part of Letters Patent No. 593,500, dated November9, 1897. A lication filed February 17,1897. Serial No. 623,799. (Nomodel.)

To all whom it may concern.-

Be it known that I, HosEA R. TILLISON, of

Boston, county of Suffolk, State of Massachin setts, have invented anImprovement in Outter-Heads, of which the following description, inconnection with the accompanying draw-J ings, is a specification, likeletters on the drawings representing like parts.

The matter of the adjustment of the several blades of a cutter-head,particularly in woodworking machinery, is of extreme importance, itbeing vital that the cutting edges of the blades should be absolutelyuniform, lying in one and the same peripheral surface or path ofmovement, as otherwise the work done by the cutter-head would be unevenand entirely unsatisfactory. However, as heretofore constructed it hasbeen exceedingly difficult to secure thisaccuracy of alinement and therequisite perfection of adjustment, particularly in woodworkingcutter-heads, in which the necessary angle or bevel of the cutting edgesof the blades is such as to require that they should be independentlysharpened and adjusted, it being customary to set one blade and thenadjust the other blades by tapping them slightly one way or another witha hammer in order to get them as nearly in proper position as possible.Even with themost experienced skill, however, this and other methods ofadjustment are unsatisfactory. To the end therefore of providing meansfor securing a quick and perfect adjustment, as well as providing animproved cutter-head having an unyielding support for the blades andimproved means of securing the latter therein, I make a cutter-head ofany desired form, providing the same with slots or recesses to receivethe blades, and between the blades and fixed rests, preferably thebottoms of the slots, I introduce adjustable alining stops foraccurately gaging the cutting edges of the blades when the latter aredropped into the slots. By this means the blades are automaticallyadjusted without any further trial. The blades are ground as desired andare then applied to a chosen standard or gage, being adjusted thereto bya screw, block, or other alining stop or adjusting means, said meansbeing preferably, as herein shown, on the blade itself. Adjustment ismade to cause the blade and its alining stop to accurately fit the gage,and this having been done the blade is simply dropped into place in itsslot and fixedly secured, the previous gaging thereof making ita'nabsolute certainty that the securing-bolts or set-screws aretightened against their sides. This part of my invention consists ofdeflecting the set screws slightly to the right, so that the forwardmovement of the screw has a downward action on the blade, therebycounteracting all tendency the latter might have to creep up in theopposite direction.

The details of my invention will be more fully apprehended in the courseof the following description, taken in connection with the accompanyingdrawings, illustrative thereof, and will be more particularly defined inthe appended'claims, which form a part of this specification.

In the drawings, Figure 1 is a perspective View showing a surface-planercutter-head embodying my invention. Fig. 2 is a transverse verticalsection thereof. Fig. 3 is an enlarged detail in horizontal section onthe line 3 3, Fig. 2. Fig. ais an enlarged detail View in elevation ofone of the cutter-blades and partly broken away in order to show thedetail arrangement of one form of adjusting means. Fig. 5 isaperspective view of one form of gage used in connection with myinvention. Fig. 6 is a detail View of a wrench used to tighten specialscrews employed for securing the blades.

For convenience of illustration and description I have herein shown myinvention applied to a cylindrical cutter such as is commonly employedin wood-planers, although I wish it understood that my invention isapplicable to any form of cutter-head.

The body a of the cutter-head is provided with a plurality oflongitudinal slots b,extending a considerable distance therein towardthe center, but in planes tangential thereto,

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as shown. These slots are carefully milled out, so as to be absolutelyuniform in depth, or are otherwise provided with rests, ledges, orabutments which are absolutely uniform in depth from the outermost edgesof the slots.

The blades are provided adjacent each end or at other intervalsthroughout their lower edges with screws adjustable therein, as shown indetail in Fig. 4. As the several blades become dull by use or otherwiseinjured they are removed from their slots and sharpened as desired.After being sharpened they are applied to a gage 6, preferably of Ushape, with one comparatively wide side 6 and an opposite parallelshorter side 6 the edge side of the blade being applied to the side e ofthe gage. The adjusting screw or stop 61 is then carefully turnedoutward until it fits exactly within the gage against the side 6 causingthe edge of the blade to just touch along the opposite side e. The screw(1 at the opposite end of the blade and others, if they are used, aresimilarly adjusted and gaged. The blade is inserted in its slot untilthe heads of the adjusting screws or stops touch the bottom thereof ofthe other rest, the blade being then set up tightly by itsfasteningscrews f. The next blade is similarly adjusted and fastened,and so on with all the succeeding blades, the result being that thecutting edges 0 of all the blades fall within one and the samecylindrical surface, being necessarily in absolutely perfect alinement,without any experimental tests whatever being required for the reasonthat each blade has been adjusted accurately by the adj usting-screwsacting as alining stops to fit one and the same unvarying gage 6.

It is not necessary to carry out my invention that the alinin g stopsshould be provided in the form of the screws d, nor that they should belocated in the blades themselves, inasmuch as any other means ofadjustment between the bottoms or rests of the slots and the sharpenededges of the blades is within the contemplation of my invention-that isto say, the screws d could be inserted in the bottom of the slot, forinstance, and used in connection with a depth-gage in the same way asthe screws on the blade are used in connection with a width-gage, or anyother means may be employed for filling up the intervening space betweenthe bottom of the slot and the lower edge of the blade or between anyportion of the blade and a fixed rest and capable of being accuratelyadjusted, so as to be capable of a predetermined measurement before theblade is dropped in place. 7

A further extreme advantage of my invention resides in the fact that itenables the cutting circle of the cutter-head to be readily maintainedunvarying, notwithstanding the grinding away of the blades in sharpeningthem, for the reason that the blades are always set to a standard gagein connection with the alining stops. As at present constructed thegrinding of the outer edges of the knives changes the cutting circle,reducing the diameter of the cutter-head, and usually necessitating thatthe presser-bar after the cut and sometimes the chip-breaker shall bereadjusted thereto. 7

By my invention the blades of the cutter are moved outwardly as they areground away, thereby keeping the cutting circle unchanged, so that thepresser-bar does not require altering.

By having the blades supported on either side by a solid wall of metal,as is shown, the slots being of a width to accurately receive thecutting-blades and extending tangentially at an angle to suit theparticular purpose for which the cutter-head is used, it will be seenthat the blade is reinforced and rendered unyielding, so that it cannotpossibly vibrate, as it would if held merely by a set-screw or clampingmeans here and there along its lengths, as is at present the practice.

I prefer to make the slots 1) of a width to permit the blades to fitclosely therein, so as to be capable of easy removal or insertionwithout looseness, thereby providing a cu tter-head capable of thefinest and most accurate work required.

Referring to Fig. 3, it will be seen that I have provided a plurality ofset-screws f for clamping the blades in fixed adjustment within theirslots 1), these screws having square ends f and socket-headsf to receivethe ends 9' of the wrench g. This construction permits the use of anextended threaded surface to give rigidity and extended holding surfacefor the screws, the screw proper being enabled thereby to occupy all thespace available, a considerable part of which would otherwise berequired to accommodate the head of the screw.

It will be observed that the screw-holes are not perpendicular to thesurface of the blades, but are slightly deflected to the right at theirouter ends, the object of this feature of my invention being topreventthe tendency of the bladesto creep up. This latter tendency isoccasioned largely by the turning of the screw against the plane surfaceof the blade, thereby producing a twisting action on the blade tendingto lift the blade and shove it out of its proper position, so that itwould result that a blade properly and accurately alined would afterwardbe found to be entirely out of adjustment when the tighteningbolts wereset up.

By my invention the downgoing or righthand edges only of the inwardlymoving screws bear against the surface 9f the blade,

thereby tending in no way to lift the blades,

asmuch as many changes and substitutionsv and modifications in detailsof construction,

arrangement, and combination of parts may be resorted to withoutdeparting from the spirit and scope of my invention.

What I claim is 1. In a cutter-head, having a removable blade, a rearabutment for the blade, a fastening-screw operating in said head endwiseagainst the side of said blade, said screw being-deflected from aperpendicular thereto so as to bear on the blade with a tendencydownward away froin'the edge of the blade when being set up,substantially as described.

2. The combination with a cutter-head provided with a plurality of reststo receive the blades, said rests being in one and the same circleconcentric with said head, and a plurality of removable blades extendingat the same angle to the center, of means to maintain unvarying thecutting circle of the cutter-head notwithstanding the sharpening of theblades, said means comprising a plurality of adjustable stops carried bythe inner edge of each blade, and an unvarying gage to which each blademay be fitted by the adjustment of its said stops before being placed'inthe head, whereby when the blades are dropped into their severalpositions the stops Will engage said rests and the cutting edges willall fall in one and the same circle, the same as previously occupied,substantially as described.

3. A gage for the purpose set forth, said gage being substantially U-shaped, and having one wide side and an opposite narrow side

